A news agency specialised in investigative reporting in the US, ProPublica, released an informative series of reports (here, here and here) on the use of body scanning technology by the Transport Security Agency, who is responsible for implementing and regulating travel security measures under the Homeland Security Act of 2002. After its 10th anniversary, many people are wondering what the TSA has actually accomplished in making airports in the US safe from terrorism. The articles focus on the use of body scanners, which are at the focal point of controversies surrounding the TSA. Early on, before the body scanners were first introduced, there was concern as to whether they could pose a significant health risk as the x-ray scanners use ionising radiation that could cause cancer in a minority of airline passengers that pass through them. This is due to the fact that since millions of people enter the scanners the probability of an unfortunate few getting cancer from the machines goes up.

“Even though it’s a very small risk, when you expose that number of people, there’s a potential for some of them to get cancer,” said Kathleen Kaufman, the former radiation management director in Los Angeles County…ProPublica

This health risk is considered low based on the amount of ionising radiation people receive from scanners, which is much less than what they receive while airborne. People receive much larger doses of ionising radiation from being bombarded with cosmic rays when travelling by air at high altitudes. In fact, pilots and flight attendants are actually classified as ‘radiation workers’. According to a study from NASA, flight routes at high latitudes potentially increase radiation exposure to passengers during solar storms. In the case of x-ray body scanners, it is one of a number of risks that air passengers must endure.

Back scatter x-ray body scanner

Millimetre wave body scanner

In the US, the problem with investigating body scanners used by the TSA is that they are classified as non-medical devices, meaning they are not evaluated by the US Food and Drug Administration who normally tests the health effects of machines that emit x-rays. Beyond the scientific research overseen by the TSA, little peer-reviewed research is available on body scanners. Like other forms of security technologies, will body scanners be withheld from scrutiny by independent researchers, including many scientists?

Prior to 9/11, state authorities were able to inspect security machines in airports, but since then the TSA is in charge of security checkpoints and have manufacturers make inspections. This may all come down to lobbying as Rapiscan, the maker of x-ray ‘backscatter’ technology, increased its lobbying expenditures from $130,000 to $420,000 in just two years. Many more body scanners will be installed in the US in the next few years. The parent company of Rapiscan, OSI Systems, saw ‘the revenue of its security division more than double since 2006 to $300 million in fiscal year 2011′. While it’s not surprising that the body scanning business is booming during a time when global scares of terrorism are frequent, seeing scanners simply as a way to keep people ‘safe’ may not only be inaccurate, but delusive.